In many instances it is necessary to exchange heat between two fluids. A good example of this is a recuperator for recovering heat as in a preheater for air from a hot liquid. Another example is the recovery of heat from a furnace gas to preheat a liquid. Thus the heat exchange system of this invention is ideally suited as a variable heat recovery system such as a recuperator for recovering heat from a furnace exhaust which in some instances may be as high as 2000.degree. F. or higher.
With the system of this invention the amount of recovered heat can be controlled in line with the heat requirements by the use of movable baffles or dampers. Thus if the exhaust is at the above 2000.degree. F. this heat can be recovered to preheat a fluid. If, however, the recovery is to heat the air for supplying heat to a worker occupied space in a factory it may be that this amount of recoverable heat would be too high and therefore only a portion will be recovered.
One of the features of this invention is to provide a variable heat exchange system that can be used to transfer heat in controlled amounts from one fluid to another by the use of movable baffles or dampers.